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Are you struggling with inaccurate and unreliable water quality measurements?

The Ohaus Starter Pen Meter ST20S is your solution, bringing the precision of Liberty Scales to the field of laboratory instruments. This compact and economical device delivers quick and precise salinity measurements ranging from 0.0 to 80.0 ppt and temperature readings up to 99.0 °C. Ideal for a wide range of applications, including pH, oxidation-reduction potential (ORP), conductivity, dissolved oxygen (DO), and total dissolved solids (TDS), this meter ensures accurate results without the bulk and complexity of traditional equipment.

Key Benefits:

  • Versatile Measurement Range: Accurately measures salinity up to 80.0 ppt and temperature up to 99.0 °C, catering to various water analysis needs.
  • High Accuracy: Ensures reliable readings with an accuracy of ± 1.5% for salinity and ± 0.5 °C for temperature, essential for precise water quality monitoring.
  • Durable and Portable: Equipped with a robust ABS housing and an IP67 waterproof rating, making it suitable for use in harsh, wet environments.
  • User-Friendly Design: Features an easy-to-read LCD and simple operation powered by 4 included 1.5V batteries, promoting efficiency in field applications.
  • Automatic Features: Includes an automatic shut-off to conserve battery life and easily replaceable electrodes for continuous performance.
  • 5-Year Warranty: Enjoy peace of mind and long-term reliability with a comprehensive 5-year warranty on your investment.

When you choose the Ohaus Starter Pen Meter ST20S, you're not just purchasing a meter but investing in peace of mind. The reliability and accuracy of this meter mean that you can trust your water analysis results, leading to better-informed decisions and consistent monitoring. Experience the convenience of having a high-quality water analysis, meter, and electrodes at your fingertips with this compact, economical solution. Feel confident in your measurements and embrace the ease of use that comes with this meticulously designed starter pen meter from Liberty Scales.

Reach out to our dedicated team for further information and personalized assistance. Call us at (661) 888-1919 or email us at We're here to help you every step of the way!


  • Meter Type: Salinity

  • Measurement Range: 0.0 – 80.0 ppt; 0.0 – 99.0 °C

  • Accuracy: ± 1.5% / ± 0.5 °C

  • Measurement Resolution: 0.1 ppt

  • Display: LCD

  • ATC: Yes

  • Temperature compensation: Automatic

  • Accuracy ± (Temperature): 0.5 °C

  • Automatic Shutdown: Yes, After 6 minutes of non-use

  • Battery Life: 200 Hours with Disposable Batteries

  • Calibration: 1 Point

  • Conductivity accuracy (±): 1.5 %

  • Conductivity measuring range: 0.0 – 80.0 ppt

  • Dimensions: 1.5 in x 7.28 in x 1.77 in (38 mm x 185 mm x 45 mm) (LxHxW)

  • Measurement Range (Temperature): 0 °C – 99 °C

  • Net Weight: 3.88 oz (110 g)

  • Number of Buttons: 3

  • Power: 4 AG13 Batteries (Included)

  • Protection Rating: IP67

  • Temperature Display: Yes

  • Temperature Range: 0 °C – 99 °C

  • Temperature Sensor: 50 KΩ NTC

  • Working Environment: 50°F – 104°F, 85%RH, non-condensing (10°C – 40°C, 85% RH, non-condensing)

  • Wrist Strap: Yes
  • Free Shipping: Available across 48 continental USA. Extra charges may apply for residential, farm, or rural areas.
  • Express Shipping: Overnight and faster shipping options available at additional costs. Quotes obtainable via email.
  • Delivery Time: Typically 5 to 7 business days, varying by location and external conditions.
  • Tracking Information: Provided via email upon shipment. Accessible through account login. Additional information available upon request.
  • Return Policy: 15-day return period for unused, original condition products. A 25% restocking fee applies. Buyer covers original and return shipping costs.
  • Customer Support: Contact at (661) 888-1919 or for queries or concerns about shipping.